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This content will become publicly available on December 1, 2025

Title: Exploring toroidal anvil profiles for larger sample volumes above 4 Mbar
Abstract With the advent of toroidal and double-stage diamond anvil cells (DACs), pressures between 4 and 10 Mbar can be achieved under static compression, however, the ability to explore diverse sample assemblies is limited on these micron-scale anvils. Adapting the toroidal DAC to support larger sample volumes offers expanded capabilities in physics, chemistry, and planetary science: including, characterizing materials in soft pressure media to multi-megabar pressures, synthesizing novel phases, and probing planetary assemblages at the interior pressures and temperatures of super-Earths and sub-Neptunes. Here we have continued the exploration of larger toroidal DAC profiles by iteratively testing various torus and shoulder depths with central culet diameters in the 30–50 µm range. We present a 30 µm culet profile that reached a maximum pressure of 414(1) GPa based on a Pt scale. The 300 K equations of state fit to ourP–Vdata collected on gold and rhenium are compatible with extrapolated hydrostatic equations of state within 1% up to 4 Mbar. This work validates the performance of these large-culet toroidal anvils to > 4 Mbar and provides a promising foundation to develop toroidal DACs for diverse sample loading and laser heating.  more » « less
Award ID(s):
2022492
PAR ID:
10517913
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Nature
Date Published:
Journal Name:
Scientific Reports
Volume:
14
Issue:
1
ISSN:
2045-2322
Page Range / eLocation ID:
11412
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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